Automatic control of conveyers.



E. H MESSITBR. AUTOMATIC CONTROL 'OF GONVBYERS. APPLIOATION FILED MAR.22, 1912 Patented Jan. 19, 1915.

5 INVENTOR mama UNITED STATES PATENT OFFICE.

EDVJILN I-I. MESSI'IER. CF BROOKLYN, NEW YORK, ASSIGNOR TO ELECl R-ICWEIGHING COMPANY, G33 NElV YORK, N. Y., A CORPORATION OF NEW YORK.

AUTOMATIC CONTROL OF CONVEYER-S.

Specification of Letters Patent.

Patented Jan. 19, 1915.

Application filed March 22. 1912. Serial No. 685,483.

{reference being had to the accompanying drawings, forming a partthereof.

This invention relates to an improvement in Weighing mechanisnnand moreparticularly to the continuous weighing of material as it is carried bya traveling conyeyer.

The object of the invention is to provide a continuous weighingmechanism arrang d to Weigh various kinds of material and to' maintain apredetermined proportion between the Weights of the various materialsconveyed.

In order oughly understood, 1 will describe an em- ..loodiment thereof,having reference to the accompanying same,- and'will then drawingillustrating the point out the novel fea tures in claims. 7

l igurc l of the accompanying drawing is v a diagrammatic view of oneembodiment of cal drums or pulleys 16.

'ior the upper run ried by a frame three kinds of material itscooperating pawls,

the invention arranged to feed and weigh simultaneously. 2iis a detailof one oi the sectors a portion of said sector being broken away to moreclearly show its con strnction.

The trave ling conveyers upon which the material to be Weighed iscarried are here shown in the form of three endless conveyor bellts 10,11 and 12. The upper runway of eachbelt is supported by suitable pulleysa, 15, preferably troughing; and the lower runway is supported byordinary cylindri- Two pulleys 15 av of the belt are carpulleys 16 aresimilarly carried by a frame 20. The frames 18 and 20 are connectedrespectively hv means of rods 21, with two weighing levers Theconnections or" the rods Ql,

22 are upon opposite sides the 'iulcr ims, or points of support A, oithe we ghing levers, whereby the two platforms or irames it '20, willcounterlmlancc the empty belt portions will also be counterbalanced.This method of counterbalancing 18, and two idler that the invention maybe thorand,

each other, and

is not claimed herein but is illustrated'for the purpose of disclosing acomplete operative machine. It is specifically described and claimed inmy Patent No. 998.974, issued July "25th, 1911.

The-left hand lever extends to the right beyond the right hand lever andthisextension 25, has pivotally connected to the end thereof a plunger26. This plunger enters a casing 27 having a mercury bath cooperatingwith a variable resistance device 28. This resistance device isdescribed and claimed in my Patent No. 1,014,604, issued January 9th,1912.

The supporting mechanisms for the belts 11 and 12 are the same as thatfor the belt 10. The resistance 28 arranged in a circuit 30 fed by angenerator 32 and also in cluding an ampere-hour meter 31-. The speed ofthe generator 32 is air 'anged to be proportionate to the speed ofmovement of the conveyer belt, a convenient method. of maintaining theproportionbeing to connect said generator in driving relation with apulley in engagement with the conveyor belt. In the arrangement of thecircuit 30 as shown, the amount of current permitted to pass through theinstrument 34 will be proportionate, first to the speed of the genoratorand second, inversely to the amount of resistance interposed in thecircuit. As the speed of the generator 32 is proportionate to the speedof the conyeyer belt, and the amount of resistance 28 interi posed inthe circuit 30 is proportionate to f the movement of the plunger 26,which movement is determine by the Weight oi the material it passes overthe platform 18, said material being fed from a hopper 36, or what ma ybe termed a master feeding device, it will then follow that theindication or registration of the instrument 3% at any moment will beexactly proportionate to the Weightcarried and the speed at which itcarried past a given point at such moment.

The conveyors ll and 12 are arranged to bc'l'ed from hoppers at) and 50,from which thdm'iaterial is discharged by motors ll and 51 respectively.the arrangement being such that the u 'hts of the materials fed from thehoppers W and hour a predetermined proportion to one another. Aconvenient example of such an arrangement would be one adapted to feedfou r parts iron ore. two parts coke. and one part of lime stone to ablast furnace, these proportions being n'iaintaincd autoimiticallyirrcspec tire of the actual quantity conveyed. To maintainautrmiatically the desired relation between the amountsof materialconveyed by the several belts, the motors 41 and 51 are arranged to havethe resistances of their field circuits controlled partly by theinstrument il and partly by mechanism con trolled by the speed oi. belts11 and 12. The motors l1 and 51. are connected to leads 60, 61 from somesuitable source of electrical supply and are provided with shunt fieldcoils 4-2. 52 connected at one end by conductors 43, 53 respectively,with one end of variable resistances 41, 54. y The amount of resistancein the shunt field circuits isvaried by contact carrying arms 45 and 55which are connected by conductors 46 and 56, re spectively, to the lead(31. The arm 45 is provided with a pair of toothed sectors 47' whichcooperate with pawls operated by magnet coils 48 and 49. The specificconstruction of these magnets and pawls is not claimed herein but isspecifically described and claimed in my application serially numbered135.481 filed herewith. The coil 48 is connected in an auxiliary circuit37 controlled by the meter 34, and the coil -19 is in an auxiliarycircuit (l2 controlled by a meter 64. The meter 64 *is connected in acircuit 65 fed by a generator 66 which is in driving relation with thebelt 11. The speed with which the belt 11 is driven and the weight ofthe material thereon determines the amount of current passing throughthe circuit 65, and this current operates the meter 61, the speed ofsaid meter being dependent upon the current passing thcrethrough. Themeter 6-1 is provided with a circuit controller, such as that describedand claimed in my application serially numbered 685,484 filed herewith,whereby the circuit 62 is periodically closed as the meter shaftrotates. Thus the number of impulses sent through the coil 49 dependsupon the rate of rotation of said meter shaft.

The arm. 55 is provided with toothed sectors 57 which cooperate withpawls operated by magnet coils 5S and 59. The coil 58 is connected in abranch of the auxiliary circuit 37 controlled by the meter 34, and thecoil 59 is in an auxiliary circuit'72 controlled by the meter 74. Themeter 7 4 is connected in a circuit 75, fed by a generator 76 which isin driving relation with the belt 19. The speed with which the belt 12is driven and the weight thereon determine the amount of current passingthrough the circuit 75, and this current operates the meter 74, thespeed of said meter being dependent on the current passing therethrough.This meter is also provided with a circuit controller, whereby thecircuit 72 is periodically closed as the meter shaft rotates.

From the foregoing it will be noted that the resistances +1 and F-lconnected to the field coils l2 and 5; respectively, are each controlledby two magnet coils, one of said coils being controlled from the meter34 in the main circuit, and the other being controlled by a circuitwhichis dependent upon the current generated by the corresponding belt, aswill be more. fully described. Thus, for example. it the hopper 36 feedsan increased amount of material .to the belt 10, the plunger 26 will beforced downward to reduce the amount of resistance 28 in the circuit3'0, thus increasing the current in said circuit and consequentlyspeeding up the meta-34. The circuit controller in said meter thereforecloses the auxiliary circuit 37 111 )16 frequently. thereby causing morefrequent impulses to be sent thr duqhthe coils 48 and 58. These coilscause the pawls connected therewith to move the sectdrs 47 and 57,respectively, to swing the arms 45 and 55 toward the left and cut inmore of the resistances 4-1 and'54. This increases the resistance in theshunt field coil circuits and causes the motors 41 and 51 to speed up.thereby feeding more material onto the belts 11 and 12. (in the otherhand, if the hopper 36 should feed less than the predetermined amount,the reduction in the weight upon the platform 18 would cause the plunger26 to be raised. thereby in creasing the amount of resistance in thecircuit 30 and. reducing the current flowing therein. The speed ofrotation of the moter 34 is consequently reduced, and conse' quently thefrequency of the impulses in the coils 48 and 58. If the frequency ofthe impulses in the coils 4-9 and 59 is then greater than in the coils48 and 58, the arms -15 and 55 are swung toward the right and reduce theresistance in the field coil circuits to reduce the speed of the motors41 and 51 andconsequently the weight of material fed to the belts 11 and12.

Similar results occur if the materials fed onto the conveyer bolts 11and 12 become for any reason too great or too little to maintain theproportional weights between them and the weight of the mdmrial passingover conveyor belt 10 in the desired proportions.

Of course the proportions of materials fed by the difi'erentconveyersmay be varied to suit different conditions. Some of the ways in whichsuchadju'stments may be made are shown in my coponding application forpatent, serially numbered 685,484 to which reference has been madebefore. The conveyors may be driven at the same rate of speed or eachmay be driven at a diflerent rate of speed. Obviously this invention mavbe applied to two or any greater number of conveye'rs.

The means for driving the conveyer belts is not shown, but in thespecific embodiment of my invention which 1 have described it may beassumedthat they are each driven at a constant rate of speed.

The usual variations in speed in the con veyer belts are compensated forby the changes of voltage which follow and in the consequent-changes ofcurrent in the meter circuits.

What I claim is:

l. A plurality of conveyers, means connected with each conveyer forgenerating an electric current proportional to the weight of material onsaid conveye'r and to the rate of movement of the conveyer, and meansactuated by the relative values of said currents for maintaining a fixedproportion between the relative rates at which materials are carried bysaid conveyers.

2. A plurality of conveyers, means connected with each conveyer forgenerating an electric current proportional to the weight of material onsaid conveyer and to the rate of movement of the conveyer, and meansactuated by the relative values of said currents for regulating theproportion of the loads carried bv said conveyers.

3. Continuous weig ling mechanism com prising a. plurality of means forconveying loads, a weighing device for each load conveying means, andmeans controlled by said weighing devices for regulating proportions ofthe loads carried by said conveying means.

'4. Continuous weighing mechanism comprising a. plurality of conveyers,a weighing device for each conveyer, and means controlled by saidweighing devices for automatically maintaining a predeterminedproportion between the loads on the conveyers.

5. Continuous weighing mechanism, comprising a plurality of conveyers,weighing means over which the conveyers are arranged to pass, a masterfeeding device for feeding material to one of the conveyers, one or moreauxiliary feeding devices for feeding material to the other conveyers,and means for proportioning the amount of material fed by said auxiliaryfeeding de vices in accordande with any variations in the amount ofmaterial fedby said master feeding device.

6. Continuous weighing mechanism, comprising a master conveying device,an electric circuit, means for proportioning the electric current insaid circuit in accordance with the weight of the material and the speedat which it is being transported,

means for measuring said current, one or more auxiliary conveyingdevices, and

auxiliary conveyers.

8. Continuous weighing'mcchanism, comprising a master conveyer, weighingmeans over which the conveyer is arranged to pass, an electric circuit,an electric quantity theter therein, means including a variableresistance device controlled by said weighing means for varying theamount of current in the said circuit proportionately to the varyingmovements of the weighing mechanism as the conveyer passes thereover, anauxi1- iary conveyer, means for feeding material to said auxiliaryconveyer, a motor for operating said feeding means, a generator indriving relation with said auxiliary conveyer, and means for varying thespeed of said motor, said speed varying means being controlled by saidquantity meter and by the current from said generator.

9. Continuous weighing mechanism, comprising a master conveyer, weighingmeans over which the conveyer is arranged to pass, an electric circuit,an electric quantity meter therein,-means including a variableresistance device controlled by said weighing means for varying theamount of current in the said circuit proportionately to the varyingmovements of the weighing mechanism as the conveyer passes thereover, anauxiliary conveyer, means for feeding material to said auxiliaryconveyer, a motor for operating 'said feeding means, a generator indriving relation with said auxiliary conveyer, a variable resistance inthe field circuit of said motor, and opposed means for operating acontact devicewhich cooperates with said variable resistance, one ofsaid opposed means being arranged in a circuit controlled by saidquantity meter, and the other of said opposed means being arranged in acircuit controlled by a quantity meter in said generator circuit.

In'witness whereof, I have hereunto set my hand this 15th day of March1912 in the presence of two subscribing witnesses.

EDWIN n, MEssIT R. VVitaesses:

F. B. Gauss, ERNEST W. MARSHALL.

